"Old
growth" describes the fourth and final stage of stand
development, following mature forest, in which the forest
canopy is generally composed of scattered remaining
trees that assumed dominance following natural disturbance
along with newly dominant, shade-tolerant trees. Other
characteristics of oldgrowth forests may include accumulated
coarse woody debris, snags and canopy gaps created by
fallen trees. Because of these features, and the presence
of an understory, old-growth forests generally exhibit
complex stand vegetation, and provide habitat for many
species. Development of old-growth forest generally
takes from 100 to 200 years, with variation depending
on forest type. The last remaining sizable area of old-growth
forest in the contiguous United States lies in the Pacific
Northwest; only a few small and isolated patches of
old-growth remain in eastern forests. However, as a
stage in stand development, old-growth forest could
also develop in eastern forests (and was present in
presettlement forests). - Victoria Mills, Project
Manager, Corporate Partnerships, Environmental Defense

LISTENING
STUDY: Some responses reference a specific age which
trees in a forest must attain to qualify as "old growth."

1.
A forest stand usually at least 180-220 years old with
moderate to high canopy closure
2. A multilayered, multispecies canopy dominated by
large overstory trees
3. High incidence of large trees, some with broken tops
and other indications of old and decaying wood (decadence)
4. Numerous large snags, and heavy accumulations of
wood, including large logs on the ground - Bureau
of Land Management

Old
growth forest: an undisturbed forest with trees that
are more than 200 years old. It is characterized by
fallen trees, trees with broken tops, and mature and
dying trees. - U.S.
Fish and Wildlife Service

Old
growth forests enrich our biodiversity and provide core
habitat for wildlife, they serve as genetic repositories
for future crop trees and they yield non-timber products
such as medicinals. And for many people old growth forests
provide unparalleled spiritual, aesthetic and recreational
values.
Old growth comprises a
set of forest conditions that should not be described
by the age class of trees alone. For example, in the
northeast, mature hardwood trees of 80-120 years of
age can satisfy many values that are ascribed to old-growth
forests even though they are still vigorously growing.
- Eric Palola, National Wildlife Federation, in testimony
to the Senate Subcommittee on Forests and Public Land
Management, October 2, 2001

The
fourth and final stage of stand development, following
mature forest, in which the forest canopy is generally
composed of scattered remaining trees that assumed dominance
following natural disturbance along with newly dominant,
shade-tolerant trees. Other characteristics of old-growth
forest may include accumulated coarse woody debris,
snags and canopy gaps created by fallen trees. Because
of these features, and the presence of an understory,
old-growth forests generally exhibit complex stand vegetation,
and provide habitat for many species. Development of
old-growth forest generally takes from 100 to 200 years,
with variation depending on forest type. The last remaining
sizable area of old-growth forest in the contiguous
U.S. lies in the Pacific Northwest; only a few small
and isolated patches of old-growth remain in eastern
forests. However, as a stage in stand development, old-growth
forest could also develop in eastern forests (and was
present in presettlement forests). - Environmental
Defense

LISTENING
STUDY: Other responses indicate that age is an important
characteristic of "old growth forests" but emphasize
that this varies with the individual tree species in
question.

I
suppose it varies by observer. I'd be comfortable with
a definition of old-growth that included something about
a fully functioning forest with trees exceeding 50%
of maximum age for each species. - Michael Snyder,
Forester

Old
growth forests are those where the average age of dominant
canopy trees exceeds half the mean pathological age
of the species, as well as those that have not had significant
human intervention (some light cutting or road building
might be acceptable). - Robert R. Bryan, Forest Ecologist,
Maine Audubon

An
old-growth forest is a forest ecosystem where the dominant
trees largely exceed the biological maturity age of
the species concerned taking into account its specific
environment and its geographical location. The temporal
dynamic of these forests is characterised by the coexistence
of living trees, senescent trees and standing dead trees
as well as the presence of fallen dead trees, lying
on the ground, showing different decomposition levels.
Those forests show little or no evidence of human disturbance.
- Canadian
Forest Service

Old
growth forests must be defined for each forest type,
such as temperate rain forest, boreal forest, tropical
rain forest, and any other major forest type. Scientists
are now recognizing that within these broad forest types,
there is enormous variability and that further definition
is required. The definition of old growth in any kind
of forest is constantly evolving as scientists get a
clearer understanding of the many variables that make
up any forest system. There is an excellent publication
that describes the challenges in defining old growth.
It's called "New Findings about Old-Growth Forests,"
and is a Science Update from the Pacific Northwest Research
Station (Issue 4, June 2003). - Susan Hammond, Executive
Director, Silva Forest Foundation

LISTENING
STUDY: Some responses reference lack of human disturbance
as a qualifying characteristic of "old growth."

Greenpeace
supports the Taiga Rescue Network (TRN) definition,
whereby the term old-growth forest can be applied to
an area in which no forestry activities have been conducted
since 1960, if the area in question measures at least
ten hectares and contains at least ten cubic meters
per hectare of the decomposing wood that is so vital
to many animal species. It is almost impossible to find
any dead trees in planted forest areas. - Oliver
Salge 2003

Forests
in the last stage of successional development after
a long period without significant disturbance. They
are generally characterized by multiple canopy layers,
variety in tree sizes and species, decadent old trees,
standing and dead woody material, and abundant ground-level
decomposition. - Northern Forest Alliance 1999

Forest
that is ecologically mature and has been subjected to
negligible unnatural disturbance such as logging, mining,
roading and clearing. The definition focuses on structural
diversity and includes forest in which the upper stratum
or overstorey is in the mature and late mature stage,
and regrowth more than 120 years old produced through
natural processes, ie. Wildfire or windstorm. - Native
Forest Network

Perhaps
the only definition of old growth that works in the
context of papermaking is: Forests that have not been
extensively disturbed by industrial logging in the past
150 years. - Susan Hammond, Executive Director, Silva
Forest Foundation

LISTENING
STUDY: Some responses reference various ecological and
structural features of forests that would indicate their
status as "old growth."

A
community with dominant trees at or near biological
maturity. The age and structure of an old-growth community
varies with species and site. Old-growth stands are
sometimes characterized by a multi-layered, uneven age
and size class structure; a high degree of compositional
and structural patchiness and heterogeneity; and significant
amounts of woody debris and tip-up mounds. - United
States Forest Service

Old
growth is best identified by certain features of the
forest. These features include increased size of trees,
large standing dead trees, fallen trees, buried wood
in various states of decay, thick forest floor, tree
lichens and a high diversity of fungi, etc. These features
all contribute to a more complicated forest structure
than the earlier successional stages of the forest,
and this results in a higher diversity of plants and
animals. - Rainforest
Action Network

Old-growth
forest-forests that contain a wide range of tree sizes
and ages, and often including a long-lived dominant
and a shade-intolerant associate, a deep, multilayered
crown canopy, large individual trees, and significant
accumulations of coarse woody debris including snags
and fallen logs. - Society of American Foresters
1991

Old-growth
forests are the fourth and final stage of stand development,
following mature forests, in which the forest canopy
is generally composed of scattered remaining trees that
assumed dominance following natural disturbance along
with newly dominant, shade-tolerant trees. Development
of an old-growth forest generally takes more than 100
years, with variation depending on forest type. An old-growth
forest exhibits these characteristics:-A
watershed-level forest of 5,000 acres or more in size,
that has been left undisturbed, and predominantly has
trees that are 200 to 1,000 years old;
-The
accumulation of coarse woody debris, snags, and canopy
gaps created by fallen trees;
-The presence of an understory consisting of a multilayered
combination of seedlings, mature trees, bushes, and
other plants, which attribute to a complex stand vegetation
pattern;
-The inclusion of numerous dead trees, both standing
and fallen, that provide essential habitat and nutrients
to plant and animal forest species;
-An ecosystem rich in biodiversity, providing habitat
for a wide variety of indigenous plant and animal species.
- Boise Cascade

Although
the ages of some [Canadian] boreal larch and black spruce
trees have been found to exceed 350 years, the unifying
feature of Canada's boreal's old-growth is generally
not age per se . . . but the set of structural
characteristics shared by many forest types in the later
stages of succession. Relative to younger stages, old
stands have trees of many ages and sizes and often have
more large canopy trees, large snags, and large downed
logs. Overall, structural diversity is highest in old
stands, and this is reflected in unique plant and animal
communities as well as high overall species richness
relative to younger stands. - Bringing Down the Boreal,
ForestEthics, 2004

LISTENING
STUDY: Other responses indicate that there are many
definitions of "old growth forests" but little agreement
on any one particular definition.

The
US Forest Service has over 100 definitions for "old
growth." The definition changes depending on whom you
ask. The "old growth" issue was raised largely as a
result of the harvesting of 1000-year-old huge towering
Douglas fir trees in the rainforests of the Pacific
Northwest. Visions of these majestic and relatively
rare trees being harvested for wood products caused
a public outcry. Today, activists are calling 100-year-old
trees of interior Canada "old growth" even though the
trees are 1/8 the size of the Pacific Northwest "old
growth" trees and are not endangered from a biodiversity
perspective. A more scientific and precise term that
Conservation International uses when characterizing
endangered woodlands is "forests of exceptional conservation
value," or FECV for short. - International Paper

Addressing
the issue of "old growth" is a challenge, given the
lack of consensus on a definition for the term: researchers
at the U.S. Forest Service found at least 114 definitions.
"Old growth" describes not only the age of the trees,
but the overall state and composition of a forest as
well.
Governmental authorities,
environmental organizations and businesses worldwide
share the goal of protecting ecologically rich ancient
forests. Exchanging information through dialogue and
scientific reporting helps to develop forest management
approaches designed to conserve the biodiversity and
cultural values of old growth forests. - Stora Enso

LISTENING
STUDY: Other responses:

There
are 100-some definitions out there, but mainly it just
means that older trees are dominant in a landscape.
- Partin 2004

Forests
that have been able to evolve for centuries and maintain
their ecological integrity. - Frank Locantore, Co-op
America